import math

coordinates = []
coordinates_new = []

def less(a, b):
    if (a[0] - center[0] >= 0 and b[0] - center[0] < 0):
        return True
    if (a[0] - center[0] < 0 and b[0] - center[0] >= 0):
        return False
    if (a[0] - center[0] == 0 and b[0] - center[0] == 0):
        if (a[1] - center[1] >= 0 or b[1] - center[1] >= 0):
            return a[1] > b[1]
        return b[1] > a[1]

    det = (a[0] - center[0]) * (b[1] - center[1]) - (b[0] - center[0]) * (a[1] - center[1])
    if (det < 0):
        return True
    if (det > 0):
        return False

    d1 = (a[0] - center[0]) * (a[0] - center[0]) + (a[1] - center[1]) * (a[1] - center[1])
    d2 = (b[0] - center[0]) * (b[0] - center[0]) + (b[1] - center[1]) * (b[1] - center[1])
    return d1 > d2

def bubble_sort(nums):
    swapped = True
    while swapped:
        swapped = False
        for i in range(len(nums) - 1):
            if less(nums[i], nums[i + 1]):
                nums[i], nums[i + 1] = nums[i + 1], nums[i]
                swapped = True

def PolygonArea(corners):
    n = len(corners)
    area = 0.0
    for i in range(n):
        j = (i + 1) % n
        area += corners[i][0] * corners[j][1]
        area -= corners[j][0] * corners[i][1]
    area = abs(area) / 2.0
    return area

def calc(xa, ya, xb, yb):
    if ya==yb:
        x=50
        y=(x-xa)*(yb-ya)/(xb-xa)+ya
        x1=-50
        y1=(x1-xa)*(yb-ya)/(xb-xa)+ya
    else:
        y=50
        x=(y-ya)*(xb-xa)/(yb-ya)+xa
        y1=-50
        x1=(y1-ya)*(xb-xa)/(yb-ya)+xa
        if (x<-50 or x>50) and (x1<-50 or x1>50):
            x=50
            y=(x-xa)*(yb-ya)/(xb-xa)+ya
            x1=-50
            y1=(x1-xa)*(yb-ya)/(xb-xa)+ya
        elif (x<-50 or x>50) and (x1>=-50 or x1<=50):
            x=50
            y=(x-xa)*(yb-ya)/(xb-xa)+ya
            if y<-50 or y>50:
                x=-50
                y=(x-xa)*(yb-ya)/(xb-xa)+ya
        elif (x1<-50 or x1>50) and (x>=-50 or x<=50):
            x1=50
            y1=(x1-xa)*(yb-ya)/(xb-xa)+ya
            if y1<-50 or y1>50:
                x1=-50
                y1=(x1-xa)*(yb-ya)/(xb-xa)+ya
    temp = ((x, y), (x1, y1))
    coordinates.append(temp)


def del_corners(x, y, x1, y1):
    if (y==y1) or (x==x1):
        if y==y1:
            if y>0:
                xa=50
                ya=50
                xb=-50
                yb=50
            else:
                xa=50
                ya=-50
                xb=-50
                yb=-50
        else:
            if x>0:
                xa=50
                ya=50
                xb=50
                yb=-50
            else:
                xa=-50
                ya=50
                xb=-50
                yb=-50
        return ((xa,ya),(xb,yb))
    elif ((y==50 and y1!=-50) or (y==-50 and y1!=50)) or ((y1==50 and y!=-50) or (y1==-50 and y!=50)):
        if x==50 or x==-50:
            xa=x
            ya=y1
        else:
            xa=x1
            ya=y1
        return ((xa,ya), (0,0))
    else:
        if (y==50 and y1==-50) or (y==-50 and y1==50):
            ya=y
            yb=y1
            if abs(50-x)+abs(50-x1)<abs(-50-x)+abs(-50-x1):
                xa=50
                xb=50
            else:
                xa=-50
                xb=-50
        else:
            xa=x
            xb=x1
            if abs(50-y)+abs(50-y1)<abs(-50-y)+abs(-50-y1):
                ya=50
                yb=50
            else:
                ya=-50
                yb=-50
        return ((xa,ya), (xb,yb))



routes = eval(input())

for i in range(len(routes)):
    calc(routes[i][0][0], routes[i][0][1], routes[i][1][0], routes[i][1][1])

for i in range(len(coordinates)):
    a = coordinates[i][0][1] - coordinates[i][1][1]
    b = coordinates[i][1][0] - coordinates[i][0][0]
    c = coordinates[i][0][0] * coordinates[i][1][1] - coordinates[i][1][0] * coordinates[i][0][1]

    for j in range(len(coordinates)):
        if coordinates[i]==coordinates[j]:
            continue
        a1 = coordinates[j][0][1] - coordinates[j][1][1]
        b1 = coordinates[j][1][0] - coordinates[j][0][0]
        c1 = coordinates[j][0][0] * coordinates[j][1][1] - coordinates[j][1][0] * coordinates[j][0][1]

        y = (a*c1 - a1*c)/(a1*b - a*b1)
        x = (-b1*y-c1) / a1
        coord = (coordinates[j][1][0]-coordinates[j][0][0], coordinates[j][1][0]-coordinates[j][0][0])
        if a*x + b*y + c == 0:
            if x >= 0 and max(coordinates[i][0], coordinates[i][1])[0] > x:
                if (x,y) not in coordinates_new:
                    coordinates_new.append((x,y))
                coordinates_new.append((min(coordinates[i][0], coordinates[i][1])))
            elif x < 0 and min(coordinates[i][0], coordinates[i][1])[0] < x:
                if (x,y) not in coordinates_new:
                    coordinates_new.append((x,y))
                coordinates_new.append((max(coordinates[i][0], coordinates[i][1])))
            else:
                coordinates_new.append(coordinates[i][0])
                coordinates_new.append(coordinates[i][1])
        else:
            coordinates_new.append(coordinates[i][0])
            coordinates_new.append(coordinates[i][1])

map = [(50, 50), (-50, -50), (-50, 50), (50, -50)]
corn = []
# coordinates_new.append((-50,50))
# coordinates_new.append((-50,-50))

center = (sum(i for i, _ in coordinates_new)/len(coordinates_new), sum(j for _, j in coordinates_new)/len(coordinates_new))

bubble_sort(coordinates_new)

for i in range(len(coordinates_new)):
    try:
        del map[map.index(del_corners(coordinates_new[i][0], coordinates_new[i][1], coordinates_new[i+1][0], coordinates_new[i+1][0])[0])]
        del map[map.index(del_corners(coordinates_new[i][0], coordinates_new[i][1], coordinates_new[i+1][0], coordinates_new[i+1][0])[1])]
    except ValueError:
        pass
    except IndexError:
        try:
            del map[map.index(del_corners(coordinates_new[i][0], coordinates_new[i][1], coordinates_new[0][0], coordinates_new[0][0])[0])]
            del map[map.index(del_corners(coordinates_new[i][0], coordinates_new[i][1], coordinates_new[0][0], coordinates_new[0][0])[1])]
        except ValueError:
            pass
coordinates_new += map

center = (sum(i for i, _ in coordinates_new)/len(coordinates_new), sum(j for _, j in coordinates_new)/len(coordinates_new))


bubble_sort(coordinates_new)

#print(coordinates_new)

print(PolygonArea(coordinates_new))